Ignition timer



Oct. 29, 1929; w, CHRYST 1,733,941

IGNITION TIMER Filed Jan. 1 1928 Patented a. 29, 1929 UNITED, I STATES PATENT OFFICE WILLIAM A. OHRYST, OF DAYTON, OHIO, ASSIGNOR TO DELOO-REMY'OORPORATION,

OF DAYTON, OHIO, A CORPORATION OF DELAWARE IGNITION TIMER Application filed January 18, 1928., Serial No. 246,688.

This invention relates to ignition apparatus for internal combustion engines, and more particularly to the control of ignition timing in response to variations in engine speed and to variations in engine load.

One object of the present invention is to provide for the control of ignition timing by means cooperating with a metal dia hragm providing one wall of a suction c amber which is connected with the engine intake passage, said means and suction chamber being located within and forming a part of the timer-housing. In carrying out this object of the invention, I provide a cam carrying shaft which isjournalled upon a portion 7 of the timer driving shaft so that it may be rotated relative thereto, and I connect the shafts by a mechanism which can be confined within the timer housing and which iscontrolled by the suction operated diaphragm referred to. Preferably the diaphragm is located in a plane parallel to the axis of the timer driving shaft and cooperates with the timer housing to provide a cover for an opening therein. A lever connected with the diaphragm is removable through the opening when the diaphragm is removed, and one arm of the lever is connected with a collar slidable along the timer drivin shaft and connected with the driving sha and cam carrying shaft so as to change the angular relation between these shafts in response to the movement of the diaphragm.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of embodiment of the presen invention is clearly shown. v Fig. 1 is in part a vertical sectional view of an ignition timer embodying the present invention and in part a diagram showing the.

- manner ofcconnecting the suction chamber of the ignition timer with the engine intake passage.

' Fi 2 is a plan view of the timer with the distrlbutor head removed, and is a view on the plane of the line 2-2 of Fi 1.

Fig. 3 is a sectional view on t e line 3-3 is a fragmentary sectional view looking 1n the direction of thearrow 4 of 25 carrying a distributor segment 26 electrically connected with the contact 24 and rotated adjacent to a plurality of distributor posts which are arranged in a circular row. One of these posts is shown at 27 and is integral with-a socket 28 for receiving a plug or terminal connector (not shown) attached to a wire leading to an engine spark plug.

The rotor block is supported by and driven by a cam carrying shaft 30 which rotates loosely about an extension 31 of a timer driving shaft 32 which is supported by a bearing provided by the tubular shank 33 of the timer housing. ,The shaft 30 is provided with a cam 34 which cooperates with a rubbing block 35 of a circuit breaker lever 36 carrying a contact 37 adapted to engage a stationar contact 38 supported by an adjustable braclzet 39 which is adjustable about the pivot stud 40 of the lever 36. A leaf spring 41 conducts current from a'terminal'42 to the lever 36 and urges the contact 37 toward the contact 38 and the rubbing block 35 toward the cam 34:" The lever 36, bracket 39 and terminal 42 are supported by a plate 43 having cars 44 by w ich the plate may be attached to the timer housing y screws 45.

.The terminal bracket 42 is ins'ulatingly supported by the plate 43 and is connected with a terminal screw 46 which is insulated from the housing; A condenser which is contained within a case 47 is attached by clip 48 and screw 49 to the plate 43. One of the condenser foils is electrically connected with the condenser case 47 and hence with the plate 43, and the other foil is connected with the terminal bracket 42 by a conductor 50.

The lower end of the cam carrying shaft 30 rests upon a shoulder 51 provided by the shaft 32 and is attached to a plate providing arms 52 each of which is adapted to cooper ate with an arm 53 of a weight 54. Each weight 54 is supported by weight plate 55 and swings around a stud 56 attached to the plate 55. A spring 57 connects a stud 58 carnected with the shaft 32 by means respon- P sive to variations in suction in the intake passage of the engine. This passage is represented diagrammatically by a carburetor 61 and an intake manifold 62. The throttle 63 of the carburetor 61 is operated by a lever 64 and a rod 65. The carburetor is provided with a passage 66 which is anterior to the throttle when closed and which is on the engine side of the throttle when the throttle is opened a substantial amount. The passage 66 is connected by a pipe 67 with an elbow 68 screwed into a cover plate 69 which forms one wall of a suction chamber 70. Another wall of the suction chamber 7 O is provided by a metal diaphragm 71 which together with the cover 69 and a bracket 72 is attached by screws 73 to the housing 20. In this way the diaphragm and cover provide a closure for an opening 74 in the housing through which certain parts of the suction operated mechanism are removable. A rivet 75 secures to the diaphragm two dished washers 76 and 77. A spring 7 8 is located between the cover 69 and the washer 76 and tends to move the diaphragm 71 toward the left as viewed in Fig. 1 until the washer 77 engages the bracket 72. The bracket 72 is provided with an aperture 78 for receiving the head 79 of the rivet 75. The head 79 is provided with a groove 80 so that it may receive the forked end 81 of a lever 82 which is pivotally connected with cars 83 provided by the bracket 72. The lever 82 includes two arms 82 each carrying a stud 84 which is received by groove 85 in a collar 86 which slides along the intermediate shaft 59. The collar 86 is provided with lugs 87 each extending into a longitudinal groove 88 in the shaft 32 and into an oblique slot 89 in the intermediate shaft 59.

The shaft 32 is driven by the engine in the usual manner and drives the intermediate shaft 59 through the lugs 87 of the collar 86. The intermediate shaft 59 drives the cam 34 through the cooperatingweights 54 and lever arms 52. As the speed of theshaft increases, the weights 54 move outwardly due to centrifugal force and move the cam 34 clockwise relative tothe shaft 32 in order to ad- Vance the timing of the ignition, the normal the influence of suction in the intake manifold 62. Therefore the spring 78 will be free to maintain the collar 86 in the position shown in Fig. 1 and the timing of the igni- 7 tion will berelatively retarded. As the throttle 63 isopened to permit the engine to increase its speed, the passage 66 will be laced in communication with the engine intake so that the pressure in the suction chamber 70 will be sub-atmospheric.- Therefore the diaphragm 71 will be moved to the right to cause the lever 82' to move-clockwise and to move the collar 86 upwardly. The oblique slots 89 are so constructed that upward movement of the collar 86 will cause the shaft 59 to move clockwise as viewed from the top of the ignition timer. Therefore the cam 34 will be rotated clockwise relative to the shaft 32 and the timing of the ignition will be advanced.

When the engine load is suddenly in creased, tending to reduce its speed, and the throttle 63 is opened to supply a greater amount of fuel to the engine, the suction in the intake 62 will be reduced; consequently the spring 7 8 will move the diaphragm 71 toward the left to a position in which equilibrium is established between the spring pressure and the pressure differential exerted by the suction in the intake tending to move the diaphragm toward the right. Consequently the collar 86 will be moved downwardly a certain amount in order to retard the ignition in amount corresponding to the load of the engine. g

It is apparent that the speed responsive centrifugal device and the suction responsive device for controlling the advancing and retarding of the timing ignition may operate cumulatively and differentially. As the speed of the engine increases, both devices may act cumulatively to rotate the cam 34 relative to the shaft 32 in such direction as to advance the timing of the ignition and vice versa as the speed decreases. There may be conditions under which the speed of the engine is increased while its load is being increased. The centrifugal device may tend to advance the position of the cam relative to the drive shaft while the suction control device may tend to retard it. Thus both devices may act differentially to control the position of'the cam 34 relative to the drive shaft 32 so that the ignition will be timed properly to correspond with the engine speed and load conditions.

One of the important features of the present invention is the provision for facilitating the repairs and replacements of the devices which control the timing of the ignition.

By removin the screw 73, the cover 69, the

diaphragm 1 and bracket 72 may be removed from the timer without disturbing the remainder of. the assembly. The studs 84 of the lever" 82 can be freed from engagement with the collar 86 while the latter remains assembled with the shaft 59. The centrifugal device may be removed from the timer without disturbing the suction responsive "device. After removing the distributor head 21 and the timer supporting plate 43 the assembly of distributor rotor 25, cam shaft 30, intermediate shaft 59 and centrifugal device connecting the shafts may be removed from the shaft 32 in assembled relation without disturbing the shaft 32 or the collar 86.

While the form of embodiment of the present invention as herein disclosed, constitutesa preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed-is as follows:

1. Ignition apparatus for internal combustion engines comprising, in combination, an interrupter, a cam for operating the interrupter, a drive shaft, a driven shaft connected with the cam, and means for connecting the shafts and for varying the angular relation between them in response to variations in engine intake suction and including a suction chamber, one wall of which is provided by a diaphragm, a collar movable along the shafts and so connected with them as to change their angular relation as the collar is -moved, and means transmitting motion from the diaphragm to the collar.

2. Ignition apparatus according to claim 1 in which the interrupter, shafts and collar are enclosed by a housing having an opening in a wall thereof, and in which the cover for the opening is provided by the suction chamber. I

3. Ignition apparatus according to claim 1 in which the interrupter, shafts and collar are enclosed by a housing having an opening in a wall thereof, and in which a unitary sub-assembly covers the opening and com- I prises the suction chamber and means for connecting the diaphragm of the suction chamber with the collar, the sub-assembly being removable from the housing while the collar remains assembled with the shafts. 4. Ignition apparatus for internal combustino engines comprising, in combination, an

' interrupter,- a cam for operating the interrupter, a drive shaft, a driven shaft connected with the cam, a collar movable along the shafts and so connected with them that one will be rotated relative to the other as the collar is moved, means responsive to variations in engine intake'suction for moving the collar and comprising a suction chamber, one

wall of which is adiaphragm, and a bellcrank lever for connecting the diaphragm with the collar.

5. Ignition apparatus according to claim 4 in which there is, provided a housing for phragm wall of the suction chamber, another wall member of the suction chamber, and in which screws passing through these parts secure these parts to the housing.

6. Ignition apparatus for internal combustion engines, comprising in combination, an interrupter, a cam for operating the interrupter, a cam-carrying shaft, an intermediate shaft, a drive shaft providing bearings for the other shafts, a speed responsive device for connecting the intermediate and camcarrying shafts and for changing the angular relation between them, a collar for con-, necting the intermediate shaft and drive shaft and having a lug extending into grooves in these shafts, one of the grodves being oblique to the axes of the shafts whereby movement of the collar along the shafts will cause one of them to rotate relative to the other, the intermediate shaft, cam-carrying shaft and speed responsive device being removable while assembled from the apparatus leaving the collar assembled with the drive shaft, and a device responsive to variations in engine intake suction for moving the collar, said device being removable from the apparatus while the collarremains assembled with the drive shaft. i

7. Ignition apparatus forinternal combustion engines comprising, in combination, a housin having an opening in a side wall thereo and supporting an interrupter, a cam for-operating the interrupter, a drive shaft, a driven shaft connected with the cam and means for connecting the shafts and for varying the angular relation between them in response to variations in en' ine intake suctlon, a unitary sub-assemb y covering the opening and providing a suctionchamber having a diaphragm and means for connecting the diaphragm of the suction chamber with the collar, the sub-assembly being removable from the housing while the colla remains assembled with the shafts.

8. Ignition apparatus for internal combustion engines comprising, in combination, an interrupter, a cam for operating the interrupter, a drive shaft, a driven shaft connected with the cam, said cam and driven shaft having bearings upon said drive shaft, a collar movable along the shafts and so connected with them that one will be rotated relative ing the diaphragm suction chamber, one wall of which is a diaphragm, and a bell-crank lever for connectwith the collar.

9. Ignition apparatus for internal combustion engines comprising, in combination, an interrupter, a cam for operating the interrupter, a drive shaft, a driven shaft connected with the cam, said cam and driven shaft having bearings upon said drive shaft, a collar movable along the shafts and so connected with them that one will be rotated relative to the other as the collar is moved, means responsive to variations in engine intake suction for moving the collar and comprising a suction chamber, said suction chamber being supported in the side wall of a housing for the apparatus, and including a diaphragm operatively connected with said collar by a bell-crank lever, saidsuction chamber providin a closure for an aperture in the wall of sai housing.

In testimony whereof I hereto afiix my signature.

' WILLIAM A. GHRYST. 

